Load-carrying vehicles

ABSTRACT

Vehicles for picking up, transporting and putting down bins, comprising rails displaceable downwardly to pass under surfaces of the bins and upwardly to raise the bins for transport. There is no obstruction between the rails so that the vehicle can push up, transport and put down their load without a reversal of direction of movement.

liiventor John Briggs Holt Bedford, England Appl. No. 816,721

Filed Apr. 16, 1969 Patented Oct. 5, l 971 Assignee National Research Development Corporation London, England Priority Apr. 19, 1968 Great Britain 18682/68 LOAD-CARRYING VEHICLES 1,849,854 3/1932 Stuebing,.lr 214/392 3,305,116 2/1967 McKee 214/392 3,381,833 5/1968 Gordon 214/392 2,008,324 7/1935 Grab 214/392 2,583,075 1/1952 Anderson et al 214/392 3,184,087 5/1965 Prindle et al 214/392 3,432,053 3/1969 Vereschagin... 214/518 X Primary Examiner-Albert J. Makay Alt0rney-Lars0n, Taylor and Hinds ABSTRACT: Vehicles for picking up, transporting and putting down bins, comprising rails displaceable downwardly to pass under surfaces of the bins and upwardly to raise the bins for transport. There is no obstruction between the rails so that the vehicle can push up, transport and put down their load without a reversal of direction of movement.

8 Claims, 10 Drawing Figs.

US. Cl 214/392 Int. Cl 1360p l/64 Field of Search ..214/390-396, 506;212/11,14;280/43.11

References Cited UNITED STATES PATENTS 1,244,783 10/1917 Ruckes 214/392 21 15 .t, AL..-

A.. LA I T L" 30 PATENTED um 5 ISTI 3,510,452

sum 2 [IF 5 V f 22 4b 2 LOAILCARRYING VEHICLES The present invention relates to load-carrying vehicles.

Vehicles are known for picking up, transporting and putting down a load such as a bin. Amongst such vehicles are forklift trucks. However, such known vehicles have the disadvantage that in the three stages of operation, i.e. picking up, transporting and putting down, there must be at least one reversal of direction of movement of the vehicle. For example, the vehicle may move towards and into cooperative relationship with the load, stop, pick up the load, move on in the same direction as that in which it approached the load, stop and lower the load. However, in order to move out of cooperative relationship with the load the vehicle must reverse away from it.

It is in object of the present invention to overcome the aforementioned disadvantage.

According to the present invention there is provided a loadcarrying vehicle including a body having four ground-engaging wheels, the body including a pair of parallel, spaced-apart rails extending longitudinally of the body and disposed within the track of the vehicle, means for raising and lowering at least the rails relative to the ground, the region between the rails being free of obstruction whereby the entire length of the vehicle may be driven over a load with the rails passing beneath downwardly facing surfaces of the load, the downwardly facing surfaces being spaced above the ground and being cooperable with the rails upon raising of the rails for the lifting and transport of the load.

The body may include a frame work comprising a plurality of arch structures disposed transversely of the vehicle and at least one longitudinal member interconnecting the arch structures, said rails being attached to the limbs of the arch structures, said means for raising and lowering at least the rails relative to the ground being arranged to act between said framework and parts of the suspensions of the wheels.

A further pair of rails may be disposed parallel to the firstmentioned pair of rails attached to the limbs of the arch structures, and means may be provided for moving said further pair of rails substantially vertically between a first position in which they lie on the first pair of rails and a second position in which they are disposed in spaced relation above said first pair of rails.

The means for moving said further pair of rails may include a ram operable on one end portion of the further pair of rails and cables trained about pulleys on said framework and arranged to cause similar movement of the other end portion of said further rails upon movement of said one end portion of said further rails.

The further pair of rails may be formed in two sections disposed in longitudinally spaced-apart relationship, one section being disposed forward of an engine for driving one pair of said wheels and the other section being disposed aft of said engine.

The suspensions of the front wheels may be independent of one another and the suspension of the rear wheels may include a structure of inverted general U-shape, the rear wheels being mounted one on each of the lower end portions of the limbs of the U-shape structure, said U-shape structure being mounted from one of said arch structures by link members pivotally connected to the U-shape structure and the arch structure-and arranged to allow movement in a general vertical direction of said framework relative to said U-shape structure. The said link members may be arranged to allow pivotal movement of said U-shape structure about a general vertical axis relative to said framework and in this case means are provided for controlling the position of the U-shape structure about the vertical axis.

Devices may be provided for engaging the load in the regions of the ends of the first-mentioned pair of rails to prevent movement of the load off the ends of the rails of the first-mentioned pair.

FIG. 1 illustrates a side elevational view of a vehicle, in accordance with the present invention, with parts omitted and broken away for the sake of clarity;

FIG. 2 illustrates a plan view of the vehicle illustrated in FIG. 1;

FIG. 3 illustrates a scrap view of a portion of FIG. 1 with the body of the vehicle in a lowered position;

FIG. 4 illustrates a view at IV-IV in FIG. 1;

FIG. 5 illustrates in detail an additional steering arrangement for use at the rear of the vehicle;

FIG. 6 illustrates in detail an alternative additional steering arrangement;

FIG. 7 is a view similar to that of FIG. 1, of a second embodiment of the invention, parts being omitted and broken away for the sake of clarity;

FIG. 8 is a view of a portion of the vehicle illustrated in FIG. 7 including an additional feature;

FIG. 9 is a view similar to that of FIG. I, of a third embodiment of the invention, parts being omitted and broken away for the sake of clarity; and

FIG. 10 is a plan view of the vehicle illustrated in FIG. 9, parts being omitted and broken away for the sake of clarity.

The vehicles illustrated in the drawings are intended for picking up, transporting and depositing bins for fruit on a fruit farm although they are not limited to this use.

The vehicle illustrated in FIGS. 1 and 2 comprises a body consisting of a body structure formed by two parallel, horizontal, spaced-apart rails I, 2, two arch structures 3, 4 bridging the rails and connected to the rails, and two longitudinal members 5, 6 extending in spaced-apart relationship between and connected to the arch structures 3, 4.

The body structure is mounted on four wheels 7-10 disposed outside the rails l, 2. The forward pair of wheels 7, 8 are carried by parallel link arrangements 12 from the arch structure 3 and are steerable.

Rams 13 acting between the arch structure 3 and one link of each of the forward ends of the rails l', 2 from the ground and also serve as springs.

Each of the rear pair of wheels 9, I0 is carried by a respective vertical arm 14 disposed outboard of the rails 1,2. The upper ends of the arms 14 are connected by a transverse tubular member 15.

The transverse tubular member 15 is carried by a single parallel link arrangement 16 mounted from the middle of the high bridge portion of the arch structure 4. A ram 17 acts between the arch structure 4 and one link of the link arrangement 16. The ram 17 is operable to select the height of the rearward ends of the rails l, 2 from the ground and also serves as a spring. The link arrangement 16 is connected by universal joints to the tubular member 15 and to the arch structure 4 so that the tubular member may both tilt, in a vertical plane, rela tive to the body structure, and be turned about a generally vertical axis for steering.

The tubular member 15 includes a differential housing 20 within which there is a differential driven by an engine 21 and driving the wheels 9, 10 through half-shafts disposed within the tubular member 3, and chains and chainwheels disposed within the arms 14. The engine 21 is carried by the tubular member 15 with the underside of its sump spaced well above the rails 1, 2, as may be seen in FIG. I.

The steering achievable at the rear wheels 9, 10 is of the order of 14 and is additional to that achieved at the front wheels 7, 8. Such additional steering is advantageous when the vehicle has to be maneuvered in a headland when moving from the space between two rows of trees to the next space between two rows of trees, that is, when making a turn in a small headland.

The body structure also carries a second pair of rails 30, 31 spaced apart from one another by a distance substantially equal to the distance between the rails l, 2.

The second pair of rails 30, 31 is disposed above the rails l, 2 and is movable vertically, whilst remaining in a common horizontal plane, between positions in which the rails 30, 31 lie on the rails 1, 2 respectively and the positions which they have in the condition illustrated in FIG. I. The rails 30, 31 may be raised and lowered by means of rams, (not shown) acting directly or by one or more rams acting through cables or chains or other convenient means. An arrangement suitable for raising and lowering the upper rails is illustrated in and described with reference to FIG. 7 of the drawings, but is omitted from FIG. 1 for the sake of clarity of other features of the vehicle.

A seat 70 for the driver is carried by a frame 71 extending forwardly from the front arch structure 3. The frame 71 also carries the controls operable by the driver. The frame 71 is disposed above the forward extension of the lower set of rails l, 2 and is spaced above them. The seat 70, frame 71 and controls are omitted from FIGS. 2 and 4 for the sake of clarity.

In operation, with no bins on the vehicle, the vehicle is driven towards a bin 40 which, as may be seen in FIG. 4, has downwardly facing shoulders 41 spaced above the bottom 42 of the bin 40 by a distance greater than the combined thickness of the upper and lower rails 1, 2 and 30, 31 when the upper rails are lying on the lower rails.

The body structure is lower by appropriate operation of the rams 13, 17 so that the rails 1, 2, (the 31 the rails 30, 31 being, at this time, lowered on the the rails l, 2) are only just spaced off or are in light contact with the ground. The vehicle is maneuvered so that the forward ends of the rails l, 2 pass under the shoulders 41 and nearly the entire length of the bin overlies the rails 1, 2.

The body structure is then raised by operation of the rams 13, 17 and the vehicle is driven towards the next bin to be picked up and is stopped as the firstly loaded bin contacts the next bin. The body structure is then lowered and the firstly lowered bin again rests on the ground. The vehicle is then driven forward, the rails passing under both bins, until the leading ends of the rails have passed fully beneath the second bin and in this condition the first bin is situated over the rails 30, 31.

In the example being described, the upper rails 30, 31 can accommodate four bins and when the fourth bin has been loaded, the vehicle is driven forwards so that the four bins all become positioned over the upper pair of rails and the upper pair of rails is then raised to the position illustrated in FIG. 1,

the bins on the upper rails 30, 31 then being disposed between the two arch structures 3, 4. When the upper rails 30, 31 and the bins thereon have been raised, the undersides of the bins are sufi'iciently far above the lower rails to allow further bins to be loaded upon the lower rails 1, 2 beneath the upper bins. The lower rails 1, 2 are long enough to accommodate six bins, one being disposed on portions of the rails 1, 2 extending rearwardly behind the rear arch structure 4 beneath the engine 21 and tubular member 15, one being disposed on the portions of the rails 1, 2 extending forwardly from the forward arch structure 3, and four being disposed beneath the bins on the upper rails 30, 31.

When the vehicle is being moved between positions of picking up a bin, the body structure is raised to the position illustrated in FIG. 1.

To deposit all the bins in a row at one place, the body structure is lowered so that the bottoms 42 of all the bins 40 on the lower rails 1, 2 contact the ground. The vehicle is then driven forwards whilst the bins remain stationary on the ground and the rear end of the vehicle passes in succession over the bins. When the foremost bin is disposed behind the rear arch structure 4, the upper rails 30, 31 are lowered so that the bottoms of the upper row of bins contact the ground and the vehicle is then driven forwards again leaving the bins in a row upon the ground.

To deposit bins in single, spaced-apart succession, as would be desired when disposing empty bins about an orchard, the vehicle is driven to the point at which the first bin is to be deposited and the body structure is lowered so that the bins on the lower rails l, 2 contact the ground. The vehicle is driven forwards so that the rails l, 2 move beneath the bins and the rearward ends of the rails 1, 2 move away from beneath the rcarmost bin. The body structure is again raised and the vehicle is driven to the next side for depositing a bin. When all the bins on the lower rails 1, 2 have been deposited, or when only one bin remains on the lower rails and that one bin is disposed aft of the rear arch structure 4, the upper rails 30, 31 are lowered. The bin-depositing procedure is then continued for bins on the upper rails 30, 31.

It is to be understood that the bins may be unloaded from the rear or from the front, that is, the vehicle may be driven forwards or in reverse during unloading, or forwards during certain portions of the unloading operation and in 'reverse during other portions of the operation.

Whilst in the above description it has been stated that the rams 13, 17 are operated in unison to raise or lower the body structure as a whole, it is to be understood that the rams 13 may be operated by themselves or the ram 17 may be operated by itself so that only the front, or the rear, respectively, is raised or lowered.

Two types of additional steering arrangements are illustrated in FIGS. 5 and 6.

In the arrangement illustrated in FIG. 5, a ram 50 acts between the arch structure 4 and the tubular member 15 to move the tubular member 15 in a horizontal plane. The ram 50 is connected at its ends by universal joints to the arch structure 4 and the tubular member 15 respectively. A tie rod 51 extends between one vertical limb of the arch structure 4 and a point on the tubular member 15 near the remote end of the tubular member 15. The tie rod 51 is connected to the tubular member and the arch structure by universal joints. In this embodiment, the ram 17 acts between the arch structure 4 and the tubular member 15 and is so disposed that contraction of the ram causes the body to be raised from the ground. The parallel links 52, 53 are connected to the tubular member and the arch structure by universal joints 54.

In the arrangement illustrated in FIG. 6, the lower link 53 of the arrangement illustrated in FIG. 5 is omitted and a yoke 60 is provided, universally connected at its apex to the arch structure and at the ends of its limbs to the tubular member 15.

In the second embodiment of the invention illustrated in FIG. 7, the upper pair of rails is formed in two horizontally spaced-apart sections which allows the engine to be disposed over the rear wheels which provides improved weight distribution. Only such description as is necessary to understand the differences between the second and first embodiments will be given.

Two parallel spaced-apart, lower rails 71 are carried by the lower ends of arch structures 72, 73, 74, 75, 76. The arch structures 73, 74, 75, 76 are united by longitudinal members 77.

The front wheels 78 are carried from the arch structure 72 by parallel links 79 and are sprung by coil springs 80 the upper ends of which bear against arms 81 connected to a transverse torque tube 82 pivotally connected to the arch structure 72.

A ram 83 acts between a frame member 84 rigidly attached to the arch structure 72 and an arm 85 connected to the torque tube 82. Operation of the ram 83 causes rotation of the torque tube and consequential raising or lowering of the forward end of the body of the vehicle. The rear end of the body of the vehicle is raised and lowered by a similar arrangement. A ram acts between the longitudinal member 77 and an arm 91 of a torque tube 92 pivotally connected to the arch structure 74. The torque tube 92 carries further arms 93 which bear on the upper end of coil springs 94 which serve as spring suspension for the rear wheel and drive unit which is connected to the arch structure 74 by parallel links 95.

The vehicle includes an upper pair of rails which are formed in two separate sections 96a and 96b located ahead of and behind, respectively, the engine 98. The rail sections 960 are carried at their forward ends by rigid arms 100 connected to a torque tube 102 pivotally connected to the arch structure 73. An arm 104 is connected at one end to the torque tube 102 and at the other end to the piston rod of a ram 106 which takes purchase on the arch structure 72. Thus, extension or retraction of the ram 106 causes rotation of the torque tube 102 and lowering or raising, respectively, of the forward end of the rail sections 96a. The rear ends of the rail sections 960 are carried by cables 108 each connected at one end to the rear end of the rails at 110 and at the other end to the point on the rail section 960 at which the arm 100 is pivotally connected thereto. The cables 108 are trained about a pulley 112 carried by the lower rails 71 and pulleys 114 carried by the arch structure 74. Vertical movement of the forward end portion of the rails sections 960 causes through the cables 108 and pulleys 112, 114 similar movement of the rear end of the rails sections 96a. As will be realized, movement of the rails sections 96a is not solely vertical because the points of pivotal connection of the arms 100 with the rails sections 96a are constrained to move over a circular arcuate path about the axis of the torque tube 102.

The sections 96b of the rails behind the engine 98 are raised and lowered by cables 120, 121 which pass over pulleys 122, 124, 126 and which are connected to a ram 128 disposed between the longitudinal members 77. The rear ends of the rails sections 96b carry rollers 130 which cooperate with vertical channels associated with the arch structure 76 for guiding the rails sections 96b and preventing foreand aft-swinging movement of the rails sections 9612.

In use, the vehicle illustrated in FIG. 7 is driven forwardly towards a bin and as the vehicle approaches the bin, the body is lowered. At this time the upper rails sections 96a, 96b are in their lowered positions resting on the lower rails 71. The vehicle is moved forwardly so that the leading ends of the lower rails pass under the downwardly facing shoulder on the bin. The vehicle is moved forwardly over the bin until the bin is disposed on the rear upper rails sections 96b which are then raised by operation of the ram 128.

The body is then raised and the vehicle moves to the next bin. The body is lowered and the vehicle is moved over the second bin until the bin is disposed wholly on the leading portion of the lower rails 71. The body is raised by operation of the rams 83, 90 and the vehicle is moved to the next bin. The body is lowered and the-vehicle moves over the third bin so that the second and third bins become disposed on the forward upper rails sections 96a with the bins abutting one another and with the rearward end of the second bin spaced just forwardly of the rearward end of the forward upper rails sections 96a. The forward upper rails sections 96a are then raised by operation of the ram 106 and the body is raised by operation of the rams 83, 90.

With the upper rails sections 96a, 96b loaded and raised relative to the remainder of the body, six bins are loaded on to the lower rails 71. The undersides of the bins on the upper rails are disposed sufficiently far above the lower rails 71 to allow bins to pass along the lower rails.

Bins are deposited in line or in single spaced-apart succession in the reverse of the order described above for picking up the bins.

It may be found desirable to provide means for preventing movement of bins off the ends of the lower, or only, pair of rails and in this case an arrangement such as that illustrated in FIG. 8 may be adopted. FIG. 8 illustrates a forward end portion of a vehicle otherwise generally similar to that illustrated in FIG. 7. Parts which are substantially the same as parts in the embodiment illustrated in FIG. 7 are given the same reference numeral but with the addition of the suffix C.

A forwardly extending arm 140 is pivotally connected at its rearward end to the frame member 84c and at its forward end has a downwardly directed tongue 142. :An upwardly extending link 144 is pivotally connected at its lower end to the arm 140 and at its upper end to one arm of a bellcrank 146 which is pivotally mounted, by means not illustrated, from the frame member 840. The other arm of the bellcrank 146 is pivotally connected through a spring-loaded telescopic link 148 to the arm 850 connected to the torque tube 820. The arrangement is illustrated in FIG. 8 with the body in the raised position and in this position the ram 830 is extended and the arm 850 is in its furthermost position in a clockwise sense about the axis of the torque tube 82C. In this position the telescopic link 148 has caused the arm 140 to lower into engagement with the forwardmost bin 150 with the tongue 142 in front of the forward end ofthe bin 150.

As the body is lowered, by retraction of the ram 83c, the arm 85c moves counterclockwise about the axis of the torque tube 82c so that the bellcrank 146 is caused to move clockwise about its pivot and the arm is raised by the link 144 to the position 140' indicated in broken lines. The telescopic link 148 is spring-loaded in order to 'take account of differing heights of bins and of the possibility that the body may not be raised to the maximum extent possible.

It will be realized that the arrangement described with reference to FIG. 8 provides for the automatic operation of the arm I40 upon raising and lowering the body without the necessity of providing a further control operable by the driver of the vehicle. A similar arrangement may be provided at the rear of the vehicle.

In cases where the overall height of the vehicle including its load has to be kept to a minimum, as may be the case when the vehicle is working in an orchard, it may be desirable to keep the distance between the bottoms of the bins on the upper rails at a distance above the tops of the bins on the lower rails less than the distance by which the bins on the lower rails are raised relative to the lower rails upon the lower bins being lowered onto and coming to rest on the ground. In this case the driver may cause the upper rails to rise relative to the body above the position normal during transport of the bin. Alternatively, this raising of the upper rails relative to the body upon lowering of the body may be achieved automatically by an arrangement such as is illustrated in FIG. 8.

In FIG. 8, the ram 106c is pivotally connected to an arm 152 carried by the torque tube 82c rather than directly on the arch structure 72 as is the case in the embodiment illustrated in FIG. 7.

It will be realized that as the torque tube 82c is rotated in a counterclockwise direction (as seen in FIG. 8) for lowering of the front end of the vehicle, so also is the arm 152 rotated in a counterclockwise direction, and, since no fluid is admitted to or withdrawn from the ram 106e, the ram I 060 acts as a link of final length and causes rotation of the torque tube 102 in a counterclockwise direction with consequential raising of the forward ends of the upper rails relative to the body.

It has been determined that below a certain distance between the region of picking up bins and the region of putting down bins, e.g. between an orchard and a packing or cold storage house, it is more economical to use a vehicle in accordance with the present invention which only has a single pair of rails and hence can carry only a single tier of bins. Such an embodiment is illustrated in FIGS. 9 and 10.

The embodiment illustrated in FIGS.'9 and 10 includes a pair of parallel, horizontal spaced-apart rails 200 carried by the lower end of the limbs of four arch structures 202, 204, 206, 208. The four arch structures are united into a rigid framework by longitudinal members which are omitted from the drawings for the sake of clarity.

The body is carried by four wheels 210. The suspension for each of the front wheels includes an arm 212 pivotally connected at one end to the arch structure 202 and at the other end to a telescopic arrangement 214, which includes a compression spring 216. The telescopic arrangement 214 is pivotally connected at its upper end to an arm 218 connected to a torque tube 220 extending transversely of the vehicle and pivotally connected to the arch structure 202. Each front wheel 210 is carried by the respective telescopic arrangement through a kingpin which allows the wheel to be turned for steering the vehicle.

A further arm 222 connected to the torque tube 220 is acted on by a ram 224 taking purchase on a frame member 226 rigidly connected to the arch structure 202. Extension or retraction of the ram 224 serves to decrease or increase the distance between the free end of the arm 218 and the rails 200 and hence to increase or decrease the distance between the front end of the rails 200 and the ground.

The rear wheels 210 are carried by an inverted U-shape structure 228 which is connected at the lower end of its limbs 230' by links 232 to the arch structure 206. A third link 233,

parallel to the links 232, extends between the middle of the transverse portion of the structure 228 and the middle of the arch structure 206. A transverse link 234 extends between the upper end of one limb 230 and a point on the arch structure 206 at the opposite side of the vehicle.

Two coil springs 236 bear at their lower ends on the arch structure and at their upper ends one on each of two arms 238 which are connected to a torque tube 240 extending transversely of the vehicle and pivotally connected to the arch structure 206.

A ram 242 operates between the arch structure 206 and a further arm 244 connected to the torque tube 240. Extension and contraction of the ram 242 causes raising and lowering, respectively, of the rear portion of the body relative to the ground.

In this embodiment, the engine 246 forms part of the sprung weight of the vehicle and is carried by the longitudinal members (not shown) which extend between and interconnect the arch structures 202, 204, 206, 208. The drive is taken from the engine through a universal joint and a shaft 248, and a further universal joint to a differential disposed in the inverted U-shape structure 228. From the differential the drive is transmitted via half-shafts and chains within the structure 228 to the rear wheels 210.

A portion only of the arrangement for steering the vehicle is illustrated in FIGS. 9 and 10. A steering wheel 250 is connected to a hydraulic valve (not shown) which controls the overall length of a hydraulic ram 252 which acts between the arch structure 204 and one arm of a bellcrank 254 to which is also connected a steering rod 256 for the right-hand front wheel 210 and a transverse steering rod 258 operating on a further bellcrank 260 to which is also connected a steering rod 262 for the left-hand front wheel 210.

Arms 264 with downwardly directed tongues 266 are provided for preventing bins moving off the ends of the rails 200. The anns 264 are generally similar to the arms 140 described above. The means for operating them is not illustrated but may be automatic as described with reference to FIG. 8 or manual.

Only the embodiment illustrated in FIGS. 1 and 2 has additional rear wheel steering but it will be understood that the other and other embodiments have the additional rear wheel steering if so desired.

In the embodiments described above, the whole of the body is raised and lowered with the lower, or only, rails. It will be understood that vehicles may be constructed in accordance with the present invention in which only the lower, or only, rails move vertically during bin raising and lowering procedures and in cases where there are two or more sets of rails, the second and further sets of rails would be movable relative to the first set of rails and the remainder of the body.

lnstead of using the particular form of bins described above, that is, with downwardly facing shoulders spaced above the bottom of the bin, flat-bottomed bins may be used which do not have such shoulders. In this case the bins would be positioned on baulks of timber or other form of standings which would space the bottoms of the bins from the ground and allow the rails to pass under margins of the bottoms of the bins. The bins would be lifted off the standings by the vehicle and deposited on other standings at the deposition location.

Whilst embodiments of the invention have been described above in use for transporting a plurality of bins, it is to be understood that a single unit load may be transported, for example, a single container or a machine such as a sprayer to be used for spraying an orchard.

lclaim:

l. A load-carrying vehicle including: a body including a framework comprising a plurality of arch structures disposed transversely of the vehicle and at least one longitudinal member interconnecting said arch structures; four ground-engaging wheels; suspension means mounting said body from said wheels; said body including a load-engaging means comprising a first pair of elongate rails disposed on parallel spaced-apart lines within the track of the vehicle and attached to the limbs of said arch structures, said suspension means being adapted to lower said body to a position wherein said first pair of rails are adjacent to the ground and to raise said body to a position wherein said first pair of rails are spaced a greater distance from the ground; the region between the first pair of rails being free of obstruction whereby the entire length of the vehicle may be driven over a load resting on the ground, with the first pair of rails passing beneath downwardly facing surfaces of the load; said downwardly facing surfaces being spaced above the ground and being cooperable with the first pair of rails for lifting and transport of the load; a further load-engaging means comprising a second pair of elongate rails disposed on spaced-apart lines within the track of the vehicle, means adapted to more said second pair of rails substantially vertically between a first position in which they are adjacent the first pair of rails and a second position in which they are disposed in spaced relation above said first pair of rails, said means adapted to move said second pair of rails including a ram adapted to operate on one end portion of said second pair of rails and cables trained about pulleys on said body and adapted to cause similar movement of the other end portion of said second pair of rails upon movement of said one end portion of said second pair of rails.

2. A load-carrying vehicle as claimed in claim I, wherein; two of said four wheels are front wheels and the other two of said four wheels are rear wheels; the suspension means associated with each of said front wheels are independent of one another; the suspension means associated with said rear wheels includes a structure of inverted general U-shaped; said rear wheels being mounted one on each of the lower end portions of the limbs of said U-shape structure; said U-shape structure being mounted from said body by link members pivotally connected to said U-shape structure and to the body end adapted to allow movement in a general vertical direction of said body relative to said U-shape structure.

3. A load-carrying vehicle as claimed in claim 2, wherein; said link members are adapted to allow pivotal movement of said U-shape structure about a general vertical axis relative to the body and means are provided for controlling the position of said U-shape structure about said vertical axis for steering the vehicle.

4. A load-carrying vehicle as claimed in claim 1, wherein; the suspension means of the front wheels are independent of one another; and the suspension means of the rear wheels includes a structure of inverted general U-shape; said rear wheels being mounted one on each of the lower end portions of the limbs of said U-shape structure; said U-shape structure being mounted from one of said arch structures by link members pivotally connected to said U-shape structure and the arch structure and adapted to allow movement in a general vertical direction of said framework relative to said U-shape "structure.

5. A load-carrying vehicle as claimed in claim 4, wherein; said link members are adapted to allow pivotal movement of said U-shape structure about a general vertical axis relative to said framework and means are provided for controlling the position of said U-shape structure about said vertical axis for steering the vehicle.

6. A load-carrying vehicle including; a framework comprising; a plurality of arch structures disposed traversely of the vehicle; and at least one longitudinal member interconnecting said arch structures; four ground-engaging wheels; load-engaging means comprised of a first pair of rails disposed on parallel spaced-apart lines within the track of the vehicle and attached to the limbs of said arch structures; means adapted to raise and lower at least the first pair of rails relative to the ground; further load-engaging means comprising a second pair of rails disposed on parallel spaced-apart lines with the track of the vehicle; means adapted to move said second pair of rails substantially vertically between a first position in which they lay on the first pair of rails and a second position in which they are disposed in spaced relation above said first pair of rails; the

region between said first pair of rails being free of obstruction whereby with the second pair of rails in their first position, the entire length of the vehicle may be driven over a load with the first pair of rails passing beneath downwardly facing surfaces of the load; said downwardly facing surfaces being spaced above the ground and being cooperable with the first pair of rails upon raising of the first pair of rails for the lifting and transport of the load.

7. A load-carrying vehicle as claimed in claim 6, wherein; said means adapted to move said second pair of rails includes: a ram adapted to operate on one end portion of said second pair of rails; and cables trained about pulleys on said framework and adapted to cause similar movement of the other end portion of said second pair of rails upon movement of said one end portion of said second pair of rails.

8. A load-carrying vehicle as claimed in claim 6, wherein; said second pair of rails is formed in two sections in longitudinally spaced-apart relationships; said vehicle includes an engine adapted to drive one pair of said wheels; said engine being disposed between said two sections of said second pair of rails. 

1. A load-carrying vehicle including: a body including a framework comprising a plurality of arch structures disposed transversely of the vehicle and at least one longitudinal member interconnecting said arch structures; four ground-engaging wheels; suspension means mounting said body from said wheels; said body including a load-engaging means comprising a first pair of elongate rails disposed on parallel spaced-apart lines within the track of the vehicle and attached to the limbs of said arch structures, said suspension means being adapted to lower said body to a position wherein said first pair of rails are adjacent to the ground and to raise said body to a position wherein said first pair of rails are spaced a greater distance from the ground; the region between the first pair of rails being free of obstruction whereby the entire length of the vehicle may be driven over a load resting on the ground, with the first pair of rails passing beneath downwardly facing surfaces of the load; said downwardly facing surfaces being spaced above the ground and being cooperable with the first pair of rails for lifting and transport of the load; a further load-engaging means comprising a second pair of elongate rails disposed on spaced-apart lines within the track of the vehicle, means adapted to more said second pair of rails substantially vertically between a first position in which they are adjacent the first pair of rails and a second position in which they are disposed in spaced relation above said first pair of rails, said means adapted to move said second pair of rails including a ram adapted to operate on one end portion of said second pair of rails and cables trained about pulleys on said body and adapted to cause similar movemenT of the other end portion of said second pair of rails upon movement of said one end portion of said second pair of rails.
 2. A load-carrying vehicle as claimed in claim 1, wherein; two of said four wheels are front wheels and the other two of said four wheels are rear wheels; the suspension means associated with each of said front wheels are independent of one another; the suspension means associated with said rear wheels includes a structure of inverted general U-shaped; said rear wheels being mounted one on each of the lower end portions of the limbs of said U-shape structure; said U-shape structure being mounted from said body by link members pivotally connected to said U-shape structure and to the body end adapted to allow movement in a general vertical direction of said body relative to said U-shape structure.
 3. A load-carrying vehicle as claimed in claim 2, wherein; said link members are adapted to allow pivotal movement of said U-shape structure about a general vertical axis relative to the body and means are provided for controlling the position of said U-shape structure about said vertical axis for steering the vehicle.
 4. A load-carrying vehicle as claimed in claim 1, wherein; the suspension means of the front wheels are independent of one another; and the suspension means of the rear wheels includes a structure of inverted general U-shape; said rear wheels being mounted one on each of the lower end portions of the limbs of said U-shape structure; said U-shape structure being mounted from one of said arch structures by link members pivotally connected to said U-shape structure and the arch structure and adapted to allow movement in a general vertical direction of said framework relative to said U-shape structure.
 5. A load-carrying vehicle as claimed in claim 4, wherein; said link members are adapted to allow pivotal movement of said U-shape structure about a general vertical axis relative to said framework and means are provided for controlling the position of said U-shape structure about said vertical axis for steering the vehicle.
 6. A load-carrying vehicle including; a framework comprising; a plurality of arch structures disposed traversely of the vehicle; and at least one longitudinal member interconnecting said arch structures; four ground-engaging wheels; load-engaging means comprised of a first pair of rails disposed on parallel spaced-apart lines within the track of the vehicle and attached to the limbs of said arch structures; means adapted to raise and lower at least the first pair of rails relative to the ground; further load-engaging means comprising a second pair of rails disposed on parallel spaced-apart lines with the track of the vehicle; means adapted to move said second pair of rails substantially vertically between a first position in which they lay on the first pair of rails and a second position in which they are disposed in spaced relation above said first pair of rails; the region between said first pair of rails being free of obstruction whereby with the second pair of rails in their first position, the entire length of the vehicle may be driven over a load with the first pair of rails passing beneath downwardly facing surfaces of the load; said downwardly facing surfaces being spaced above the ground and being cooperable with the first pair of rails upon raising of the first pair of rails for the lifting and transport of the load.
 7. A load-carrying vehicle as claimed in claim 6, wherein; said means adapted to move said second pair of rails includes: a ram adapted to operate on one end portion of said second pair of rails; and cables trained about pulleys on said framework and adapted to cause similar movement of the other end portion of said second pair of rails upon movement of said one end portion of said second pair of rails.
 8. A load-carrying vehicle as claimed in claim 6, wherein; said second pair of rails is formed in two sections in longitudinally spaced-apart relationships; saiD vehicle includes an engine adapted to drive one pair of said wheels; said engine being disposed between said two sections of said second pair of rails. 